Many of your athletes (and other students) will be tempted to use a
wide variety of supplements in an attempt to improve their appearance,
muscle mass, strength and/or sports performance.

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The most popular supplements are vitamins and minerals, protein
powder/shakes, amino acids, and creatine. But a plethora of other pills,
powders and potions are also available to them.

THE RESEARCH SAYS

Supplements are the topic of major conversation in fitness centers,
physique magazines, and web forums. And there's no shortage of gym
"gurus," at-home chemists, and Internet "experts"
who are all too eager to offer advice. Of course, anecdotal reports are
one thing and scientific studies are another.

Let's take a look at what the research says about the
perceived benefits and safety of some popular supplements.

BORON

Athletes have used boron in the belief that it would increase their
muscular size and strength. A study cited by the supplement industry
showed that boron increased the concentration of serum testosterone as
much as 300%. What the promoters didn't mention was that the
subjects were postmenopausal women whose testosterone levels were quite
low. In fact, the women hadn't received adequate boron intake for
the previous 119 days prior to the supplementation.

In a study that involved 19 male bodybuilders, the researchers
concluded that boron supplementation had little effect on total
testosterone, lean-body mass, and muscular strength.

In general, low doses of boron are safe. But high intakes may cause
loss of appetite, nausea, vomiting, and diarrhea.

CAFFEINE

Perhaps the most widely used drug in the world is caffeine.
It's a stimulant of the central nervous system and a component of
tea, coffee, chocolate, and soft drinks as well as pills to lose weight
and combat drowsiness.

Numerous laboratory studies have shown that caffeine improves
performance in cycling and running for durations of roughly 5-20
minutes. But studies done outside a laboratory have found mixed results.
At this time, for example, it doesn't appear that caffeine improves
sprint performance (inside or outside a laboratory).

When consumed in low doses, caffeine doesn't pose any serious
risks; in high doses, it has the potential for many side effects such as
anxiety, jitters, tremors, inability to focus, gastrointestinal
distress, diarrhea, insomnia, irritability, and "withdrawal
headaches."

Since caffeine is a potent diuretic--which increases the production
of urine--it can increase the risk of dehydration. This is a major
concern during physical activity, especially in a hot, humid
environment.

CHROMIUM

An essential mineral, chromium plays a role in the metabolism of
carbohydrates and fat and helps maintain blood-glucose levels. It's
believed that chromium decreases body fat and increases muscle mass but
there's little scientific evidence to support this.

In a study that involved 95 healthy subjects, for example, a group
that received chromium didn't significantly reduce body fat more
than a group that received a placebo.

One study did find that chromium increases muscle mass. In that
study, however, muscle mass was estimated from anthropometric
measurements, which can be unreliable. And it appears as if chromium
doesn't increase muscular strength, either. In one study, a group
that received a placebo actually increased their strength more than a
group that received chromium.

Interestingly, the researchers also found that the subjects who
received chromium had urinary chromium losses that were nine times
greater than the subjects who were given the placebo.

CLENBUTEROL

This veterinary drug is used illegally to increase muscle mass in
show animals such as cattle, pigs, and sheep. Because of its proven
effects in animals, clenbuterol has been marketed to those who are
trying to achieve the same success. However, there's no evidence
that the drug increases muscle mass in humans.

In 1990, 135 people were hospitalized in Spain for eating beef
liver that contained residues of clenbuterol. Their symptoms included a
rapid heart rate, muscle tremors, headaches, dizziness, nausea, fever,
chills and insomnia.

In one study, researchers analyzed telephone calls that were placed
over a nine-year period to the anti-poison center in Marseilles, France.
Of the 51 cases that had to do with the use of doping substances, 14
involved clenbuterol. Remember, these were calls to an anti-poison
center.

Clenbuterol is a banned substance that isn't legally available
in the United States. As recently as the 2004 Summer Olympics in Athens,
two Eastern European athletes were sent packing after their drug tests
showed traces of clenbuterol.

DEHYDROEPIANDROSTERONE

Since it's a precursor to steroids, dehydroepiandrosterone
(DHEA) is believed to increase the production of testosterone, but this
hasn't been proven by research.

In one study, subjects who received a 50-milligram dose of DHEA
didn't increase their levels of testosterone. In another study,
subjects who received 150 milligrams of DHEA per day didn't improve
their body composition or muscular strength.

Since DHEA is a precursor to steroids, it's no surprise that
it has the potential for similar side effects. There are reports of hair
loss, growth of facial hair and voice deepening in women, as well the
appearance of female-like breasts in men (which isn't reversible).

DHEA may also increase the risk off uterine and prostate cancer.
Understand that this or any other steroid precursor could cause an
athlete to fail a test for steroids.

DHEA is available over the counter; it's not subject to
government regulation. It has, therefore, the potential for inaccurate
dosage and impurities. Independent testing of 16 DHEA products found
that only eight (50%) contained the exact amount of DHEA that was stated
on the labels, and the actual levels varied as much as 150%. Amazingly,
three (18.75%) of the 16 products didn't contain any DHEA
whatsoever.

EPHEDRA

An herbal form of the powerful stimulant ephedrine, ephedra (or ma
huang) is marketed as a weight-loss aid. Ephedra is often used with
caffeine and aspirin--sometimes referred to as an "ECA
Stack"--to optimize its fat-burning and stimulant effects.

This combination is found in many "energy" drinks and
weight-loss products. Some athletes consume these concoctions prior to a
workout to get "instant energy." But this practice can have
dire consequences since ephedra increases the heart rate and blood
pressure.

Needless to say, it isn't a good idea to artificially elevate
the heart rate and blood pressure and then do some type of physical
training which elevates them even more.

Other side effects include insomnia, anxiety, palpitations,
jitteriness, and irritability. More importantly, at least 100 deaths are
associated with the use of ephedra-containing products. Dietary
supplements that contain ephedra have been banned in the United States
since April 2004.

GAMMA HYDROXYBUTYRIC ACID

Yet another illegal substance is gamma hydroxybutyric acid (GHB).
Promoters claim that GHB stimulates the production of human growth
hormone and, thus, produces an increase in muscle mass and a loss of
weight. GHB is also known as "liquid ecstasy" and, because of
its sedative powers, is used as a "date-rape" drug.

When consumed in low doses, GHB can cause drowsiness, dizziness,
nausea, and visual disturbances; in high doses, it can cause
unconsciousness, seizures, slowed rate and depth of breathing, and
comas. In 2000, nearly 2,500 were hospitalized due to overdoses of GHB.
And since 1995, more than 70 people have died after taking GHB.

HUMAN GROWTH HORMONE

It's thought that human growth hormone (HGH) stimulates
protein synthesis. As a result, HGH has attracted some attention from
the athletic community.

It is a prescription drug. Over-the-counter products are available,
but they're precursors of HGH and there's no evidence that
these precursors are effective at improving muscle mass.

One study that's often cited by the supplement industry uses
prescription HGH. The study found that HMB increases lean-body mass and
decreases body fat ... in men who were more than 60 years old. There
have been very few studies of HGH on younger individuals.

Since no legitimate studies have been published on over-the-counter
HGH, its safety and efficacy are unknown. Prescription HGH has the
potential for several side effects including glucose intolerance and
insulin resistance as well as cardiovascular conditions.

HYDROXYL METHYLBUTYRATE

A relative newcomer to the supplement ranks is hydroxyl
methylbutyrate (HMB). It's a metabolite of leucine (a
branched-chain amino acid).

HMB has been promoted as a supplement that increases strength and
lean-body mass, supposedly by preventing the breakdown of muscle tissue.
This, however, has no scientific proof.

One study did support the theory that HMB may prevent muscle
damage. But the study didn't examine whether or not HMB increased
strength and lean-body mass.

In a study that did look at this aspect, subjects who received HMB
increased their upper-body strength more than subjects who received a
placebo, but the same wasn't true for their lower-body strength.
Also of note is that a supplement company sponsored the study.

Research on HMB has found minimal performance enhancement in
untrained individuals and almost none in trained individuals. In a study
that involved 26 collegiate football players, HMB didn't produce
any performance benefits. It appears as if HMB is safe when taken for
eight weeks or less.

NITRIC OXIDE

Another relative newcomer is nitric oxide, which has been promoted
by the supplement industry as a performance-enhancing substance.
Previously, nitric oxide was best known as an air pollutant (formed when
nitrogen burns such as in automobile emissions). Nitric oxide is
actually a gas, though not to be confused with nitrous oxide or
"laughing gas."

In the body, nitric oxide has numerous functions. For one thing, it
signals the body to dilate blood vessels, thereby increasing blood flow.
In addition, nitric oxide is an important neurotransmitter that relays
messages between nerve cells.

Be that as it may, this doesn't mean that there's any
benefit to taking nitric oxide as a supplement. At the present time, no
scientific research has shown that nitric oxide improves physical
performance.

RIBOSE

The breakdown of Adenosine Triphosphate (ATP) is the primary--and
immediate--source of energy that's used to perform muscular work.
Since a limited amount of ATP can be stored, it must be resynthesized
(or rebuilt) over and over again. In the body, ribose is a sugar that
helps to resynthesize ATP. In theory, then, ribose supplements could
increase the levels of ATP and improve performance.

One study showed that there was no significant difference between
ribose and a placebo in peak power, average power, and percent decrease
in power during 30 seconds of all-out sprinting on a stationary bicycle.

The fact of the matter is that the vast majority of research
hasn't found any significant enhancement of performance from
ribose.

SODIUM BICARBONATE

Also known as "baking soda," sodium bicarbonate has a
wide range of applications such as treating acid indigestion, whitening teeth, and absorbing odors in refrigerators. But it's also been
touted as an agent that delays the onset of fatigue.

A great deal of research has shown that sodium bicarbonate improves
performance. In one eight-week study, a group that consumed sodium
bicarbonate before each session of interval training had significantly
greater improvements in lactate threshold and endurance than a group
that consumed a placebo.

Now for the bad news: Likely side effects from sodium bicarbonate
include gastrointestinal disturbances such as nausea, vomiting,
diarrhea, and flatulence. Sodium citrate is thought to have the same
benefits as sodium bicarbonate without the side effects. But in one
study, eight of nine subjects (elite athletes) who received sodium
citrate experienced gastrointestinal distress.

THE LAST REP

Coaches must be aware of the many supplements that might be used by
their athletes. This is no small task since new supplements come and go
like the soup of the day.

As you can see, most supplements offer more hype than hope.
Remember, your athletes are prime targets for modern-day snake oil
salesmen who peddle pills, powders and potions.

Matt Brzycki, the Coordinator of Recreational Fitness and Wellness
at Princeton University, has authored, co-authored or edited 15 books
including Dumbbell Training for Strength and Fitness.

By Matt Brzycki, Coordinator of Recreational Fitness and Wellness
Princeton University

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